Oracle Active Data Guard - Overview

Transcription

1 <Insert Picture Here> Oracle Active Data Guard - Overview Greg Walters Sr. Technology Sales Consultant INOUG April 28, 2011 Copyright 2011, Oracle Corporation and/or its affiliates

2 Agenda Oracle Database High Availability Data Guard Overview Active Data Guard Details Customer Deployments Summary & Resources 2

3 Traditional High Availability Expensive, Idle Redundancy Idle Failover Server Production Server Redundant systems & storage Impossible to know if it all works until you try to failover 3rd party cold failover cluster Idle Disaster Recovery Systems 3rd party remote mirroring 3rd party backup software Storage Array 3rd party volume manager and file system Matching Storage Array 3

4 Oracle s HA Design Principles Complete Minimize all planned and unplanned downtime Offer a standard validated platform for maximum availability Application oriented Protect and recover application objects Enable online application changes Scale-out model Low-cost commodity hardware All components active in a grid infrastructure Integrated and simple Built-in HA with pluggable components Automatic - eliminate manual processes 4

5 Oracle Maximum Availability Architecture Low-cost, Integrated, Fully Active, High ROI Oracle Real Application Clusters Oracle Secure Backup Oracle Active Data Guard Data Guard Automatic Storage Management Oracle Recovery Manager - Fast Recovery Area 5

6 Oracle Maximum Availability Architecture Eliminate Planned Downtime Undo Human Error Online Application Upgrades Real Application Testing Online Database Changes Add/Remove Servers and Storage Database Rolling Upgrades 6

7 Jon Waldron Executive Architect Commonwealth Bank of Australia High availability is absolutely essential for us we now use Oracle RAC for instance failover, Data Guard for site failover, ASM to manage our storage, and Oracle Clusterware to hang the whole thing together Oracle Corporation 7

8 Agenda Oracle Database High Availability Data Guard Overview Active Data Guard Details Customer Deployments Summary & Resources 8

9 What is Oracle Data Guard? Best Data Protection and Availability for Oracle Databases Primary Site Data Guard Standby Site Data Guard SYNC / ASYNC Physical or Logical Standby Database Primary Database Data Guard Broker 9

10 Data Guard Architecture Simple, Integrated, Reliable, Fast Primary Database Remote Replica 1 Oracle Instance SYNC or ASYNC Oracle Instance 3 2 Oracle Data files Recovery data Automatic outage resolution 4 Oracle Data files Recovery data 10

11 Data Guard Redo Apply Rate Extreme Performance on Exadata Two Terabytes/hour 11

12 Data Guard Essential for High Availability Data Guard Capabilities 1. Built-in Oracle integration: ensures transactional consistency 2. Extremely high performance 3. Transparent operation, supports all Oracle features and data types 4. Application-integrated failover 5. Combined HA/DR solution LAN & MAN deployments provide Local HA and DR 6. Loosely coupled architecture: ensures fault isolation 7. Protection from data corruptions 8. Ensures zero data loss 9. DR servers can be utilized for testing while providing DR 10.Addresses both planned and unplanned downtime 11.No vendor lock-in for storage Extend to a Wide Area Network and add remote DR 12.Minimal network consumption 13.No distance limitation 12

13 Agenda Oracle Database High Availability Data Guard Overview Active Data Guard Details Customer Deployments Summary & Resources 13

14 Data Guard Standby Database: Failover Target Real-time Reporting Read-write Workload Fast Incremental Backups Continuous redo shipping, validation & apply Production Database Physical Standby Database 14

15 Active Data Guard Standby Database: Offload Production + Failover Target Read-write Workload Real-time Reporting Fast Incremental Backups Continuous redo shipping, validation & apply Production Database Active Standby Database (physical standby open read-only) 15

16 Sue Merrigan Director, Information Management Intermap Technologies Oracle Active Data Guard was a quick win. We easily dualpurposed our ten terabyte standby database for both disaster protection and for secure read-only access to our public-facing ecommerce applications Oracle Corporation 16

17 Active Data Guard Use Examples Education Report student grades, campus directory, course catalogs, Financial View past transactions, market prices, archived statements, Healthcare Access medical records, search doctors, facilities, Legal Access legal reports, trial histories, jury verdicts, Telecommunications View usage history, unused minutes, billing rates, Transportation Track packages, view delivery rates, Web-business Browse catalogs, web downloads, enquire order status, Bottom Line Most businesses require significant number of read-only operations Use Active Data Guard to: Offload these operations to physical standbys, and thus Unlock additional processing power of the production database 17

18 Active Data Guard Reader Farms Unlimited Read Scalability, with DR Queries Updates Scalable Reader Farm Queries Queries Queries Production Database Up to 30 active standby databases Flexible options to scale read performance Add more single-node active standby databases, or Scale an active standby database using Oracle RAC 18

19 Active Data Guard - Scale all Workloads Utilize Primary and Standby Databases Transactions / sec Double read-write throughput R/O R/W 2,610 standby 1, Primary Only Increase read-only throughput by 70% Eliminate contention between read-write and read-only workload primary Primary and Standby Simplify performance tuning 19

20 Data Guard vs. Active Data Guard Zero Impact to Recovery Time Objective (RTO) Data Guard 11g Active Data Guard 11g Stop redo apply at 8am Open read-only for queries Redo apply is always on Always open read only By 4pm, data on physical standby is 8 hours old Queries and reports always see latest data Any failover will be delayed due to backlog of data that must be applied Failover is immediate when needed, standby database always up-to-date 20

21 Maintain Recovery Time Objective Even at Very High Recovery Rates No significant performance impact on redo apply when apply instance is simultaneously open read-only 21

22 Enabling Active Data Guard Using SQL*Plus If physical standby database is shutdown Open database read-only and start redo apply SQL> STARTUP; SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE 2 USING CURRENT LOGFILE DISCONNECT; If Redo Apply is running Stop redo apply, open database read-only, restart redo apply SQL> 2 SQL> SQL> 2 ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL; ALTER DATABASE OPEN READ ONLY; ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT LOGFILE DISCONNECT; 22

23 Enabling Active Data Guard Using Data Guard Broker Oracle Database 11g Release 1 DGMGRL> edit database ADG set state= apply-off ; SQL> alter database open read only; DGMGRL> edit database ADG set state= apply-on ; Oracle Database 11g Release 2 SQL> alter database open read only; The Broker will automatically stop Redo Apply and the restart it after the open has completed 23

24 Confirming Active Data Guard is Enabled Verify whether physical standby open read-only and Redo Apply is running: SQL> SELECT OPEN_MODE FROM V$DATABASE; OPEN_MODE READ ONLY WITH APPLY Oracle Database 11g Release 2 24

25 Determining Query Latency Manually Monitor and Respond to Apply Lag Query V$DATAGUARD_STATS to calculate lag SQL> SELECT name, value, datum_time, time_computed 2 FROM V$DATAGUARD_STATS WHERE name like 'apply lag'; NAME VALUE DATUM_TIME TIME_COMPUTED apply lag :00:00 09/25/ :14:11 09/25/ :14:11 New 11.2 V$STANDBY_EVENT_HISTOGRAM view SQL> SELECT * FROM V$STANDBY_EVENT_HISTOGRAM 2 WHERE NAME = 'apply lag' AND COUNT > 0; NAME TIME UNIT COUNT LAST_TIME_UPDATED apply lag 0 seconds /25/ :20:02 apply lag 1 seconds /25/ :15:09 apply lag 2 seconds 16 09/25/ :20:58 apply lag 3 seconds 4 09/25/ :15:56 25

26 Active Data Guard Query SLA Automatically Monitor and Respond to Apply Lag Pre-configure the maximum apply lag allowed Data Guard automatically enforces the limit you set Query receives error if apply lag exceeds SLA Applications can be coded to redirect query to primary database to satisfy SLA Read/Write Workload Primary Database Real-time Reporting Continuous redo shipping, validation & apply Active Standby Database Oracle Database 11g Release 2 26

27 Query SLA Options Session setting: STANDBY_MAX_DATA_DELAY NONE: queries will be executed regardless of apply lag (Default) Non-zero (seconds): queries will be executed only if the apply lag is less than or equal to STANDBY_MAX_DATA_DELAY. If delay setting exceeded an error is returned ORA-03172: STANDBY_MAX_DATA_DELAY of 2 seconds exceeded Application then decides what to do. Zero: queries guaranteed to return the exact same result as if the query were issued on the primary database, otherwise the error ORA is returned Requires Maximum Availability and Real-Time Apply 27

28 Enabling an SLA Use a logon trigger to set the maximum delay whenever a user logs into the standby SQL> connect sys/oracle@prod as sysdba Connected. SQL> CREATE OR REPLACE TRIGGER hr_logon_set_sla_trigger 2 AFTER LOGON ON hr.schema 3 BEGIN 4 IF (SYS_CONTEXT('USERENV','DATABASE_ROLE') 5 IN ('PHYSICAL STANDBY')) 6 THEN 7 execute immediate ALTER SESSION SET STANDBY_MAX_DATA_DELAY=2; 8 END IF; 9 END; 10 / Trigger created. 28

29 Routing User Connections Role Transitions Switchover or failover At the Active Data Guard standby (new primary) User connections to read-only services are disconnected Read-write services appropriate to primary role are enabled automatically when standby becomes primary Any services not appropriate for primary role are stopped Clients connect to primary services At the new Active Data Guard standby (old primary) Read-only services are enabled automatically Clients connect to read-only services Simplified using role-based database services New in Oracle Database 11g Release 2 Replaces triggers used to start/stop services in previous releases Requires Data Guard Broker 29

30 Applications & Active Data Guard Pure Read-Only Application Model Real-time Queries selects Production Database Physical Standby Database Application directs read-only access to the standby 30

31 Applications & Active Data Guard Three Read-Mostly Application Models Real-time Queries DML 1 Selects / DML 2 Production Database DML via DBlink 3 DML via DBlink Physical Standby Database 1. Application redirects writes to primary 2. Writes redirected to primary via database link 3. Writes redirected to a separate database via a database link 31

32 Creating DBlinks for the Standby DBlinks used by the standby to redirect writes to the primary, are created on the primary and propagated to the standby via redo On the Primary SQL> CREATE DATABASE LINK sales_prmy USING sales_rw'; On the standby SQL> insert into values (999,'SMITH','GEEK',999,sysdate,1,0); SQL> commit; SQL> select * from emp where empno=999; EMPNO ENAME JOB MGR HIREDATE GEEK OCT-07 SAL COMM SMITH 32

33 Active Data Guard Auto Block Repair High Availability by Repairing Corruptions Online Automatic Block Repair When Oracle detects corrupt blocks at the primary database, it will repair online by copying the good version from an active standby database (and vice versa) Transparent to the user and application Read/Write Workload Real-time Reporting Continuous redo shipping, validation & apply Primary Database Active Standby Database Oracle Database 11g Release 2 33

34 Active Standby Performance Statistics Standby statspack in Oracle Database 11g Uses DBlink to write back to the primary database Create stdbyperf user on primary Add standby databases and instances Execute snaps Generate reports Requires perfstat user and statspack installation See Support Note In-memory Active Session History (ASH) support for real-time stats for Active Standby Database Included in Oracle Database 11g Release 2 Available via back port for Oracle Database

35 Agenda Oracle Database High Availability Data Guard Overview Active Data Guard Details Customer Deployments Summary & Resources 35

36 Amazon.com High Availability Integrated with Disaster Recovery With Data Guard HA/DR Database failover: 20 secs Apps redirected: 2 mins Standby site distance: 15 miles Before Data Guard Data Guard Automatic Failover 36

37 Intermap Technologies Inc. Active Data Guard - Secure Access to Real-time Data Use Active Data Guard to offload public Internet access to high-res 3D digital data - Auto Safety & Fuel Efficiency - Insurance Flood Modeling - Global Positioning Systems - Environmental Planning - Wireless Communications Real-time data synchronization through Data Guard Ingest geo-spatial data 10 TB Primary Database With Active Data Guard 11g 10 TB Active Data Guard Standby Database Better performance Secured Internet access 24x7 - standby always up-to-date Quick win! Easy to implement Utilize existing DR system 37

38 Apple Inc Reader Farm Scale Out using Active Data Guard Primary Database ADG 1 ADG 2 SYNC ASYNC ADG 3 ADG 8 ADG 9 L o a d App 1 B a l a n c e r App 3 App 2 App n Data Guard Standby Database (Max Availability Mode) Oracle Database 11g Release 1 38

39 MorphoTrak Cut $100,000 in System Cost with Active Data Guard Site A Read-write transactions Primary Database 2-node RAC Oracle Site B Read-only transactions Data Guard Maximum Availability - SYNC Zero data loss - automatic database failover Printrak Biometrics Identification 15 Terabyte database Mixed OLTP read intensive Active Data Guard Standby Database Read-only transactions directed to active standby Full utilization reduces acquisition cost Simpler deployment reduces admin cost 39

40 Agenda Oracle Database High Availability Data Guard Overview Active Data Guard Details Customer Deployments Summary & Resources 40

41 Summary Validating Oracle s HA Design Principles 1. Complete A validated next-generation platform 2. Application oriented Integrated application failover, online application changes 3. Scale-out model Basis of Oracle s grid infrastructure 4. Integrated and simple Database with built-in HA capabilities 41

42 Resources: HA & Active Data Guard Best Practices, Oracle Tools and Applications Maximum Availability Architecture (MAA) Active Data Guard Best Practices OpenWorld 2009: Oracle Active Data Guard Best Practices Active Data Guard Hands-On Lab Oracle Business Intelligence Enterprise Edition Offload queries to active standby Oracle TopLink Applications Easily retrofit TopLink Applications to utilize an active standby PeopleSoft and E-Business Suite Applications Transparently redirect read-only queries/reports to active standby planned for future release Prototypes demonstrated at OpenWorld

43 Questions

44 Appendix GoldenGate vis-a-vis Active Data Guard Data Guard vis-à-vis Storage Remote-Mirroring 44

45 Oracle GoldenGate The Oracle Solution for Information Integration Best-in-class real-time data replication Real-time information Flexible solution for minimal/zero downtime upgrades and migrations Over 500 customers with 4,000+ implementations Real-time Access 45

46 High Availability for Oracle Database When to Use Active Data Guard vs. GoldenGate Disaster Recovery / Data Protection Active Data Guard: simple full Oracle Database protection High-performance, simple, drop-in solution for HA and DR, readable at standby Zero data loss, integrated data corruption protection, switchover / failover DR for all data types & apps including packaged apps that can t be changed Information Distribution, Flexible HA GoldenGate: heterogeneous, active-active, migrations Heterogeneous replication, transformations, subsetting, multiple topologies All sites fully active (read/write): avoid or manage conflicts at application level Enable minimal downtime app migrations with 2nd database copy 46

47 Complementary Technologies DR, Production Offload, Heterogeneous Replication Read-write Transactions Production Database Active Data Guard Read-only Workload Data Guard Standby (GoldenGate Source*) Capture Source Trail Target Trail Delivery GoldenGate Targets * GoldenGate archive log mode (ALO) 47

48 Complementary Technologies New Environment Old Environment Minimizing Planned Downtime Active Data Guard - continuous redo shipping, validation & apply Old Production Database Data Guard Standby Database (GoldenGate Source*) GoldenGate Heterogeneous Replication (sync prior to cutover) Capture Source Trail Target Trail Delivery Data Guard - continuous redo shipping, validation & apply Data Guard Standby Database New Production Database * GoldenGate archive log mode (ALO) 48

49 Storage Remote-Mirroring Production DBMS Control Files Online Logs fil Archive Logs Updates Network I/O Standby Files Control Files Online Logs fil Archive Logs Flashback Logs Flashback Logs Data Files Data Files SYSTEM USER TEMP UNDO SYSTEM USER TEMP UNDO 49

50 Data Guard Database-Aware Transport and Apply Production DBMS Control Files Online Logs fil Archive Logs Updates Flashback Logs Data Files Standby DBMS Network I/O Oracle apply Oracle validation 7X less volume* 27X fewer network I/Os* SYSTEM USER TEMP UNDO * 50